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How to disable only the fuel pump?

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Old 03-02-2017, 09:09 AM
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How to disable only the fuel pump?

I want to run it on fuel injector cleaner through the rail (the Echlin kit). I need to disable only the fuel pump.

Any tips?

Last edited by Tootie Pang; 03-02-2017 at 09:16 AM.
Old 03-02-2017, 10:06 AM
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Re: How to disable only the fuel pump?

pull the fuse..
Old 03-02-2017, 10:19 AM
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Re: How to disable only the fuel pump?

which fuse? That 20A inline?


Old 03-02-2017, 11:04 AM
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Re: How to disable only the fuel pump?

Nope , not the 20A inline fuse .

See how it feeds not only the fuel pump , but feeds the ECM as well ? If you pull that fuse your ECM will loose power and I doubt it will run the injectors with that fuse missing (try it , I could be mistaken but I'm pretty sure the ECM won't function without that fuse) .

If that fuse does kill the ECM so you injectors won't pulse , the next thought would be to unplug both the fuel pump relay and the pump's oil pressure switch , both really easy to get to , and that will kill your pump (and if you have the "all in one" pressure switch/gauge sender the oil gauge won't function while it's unplugged) without killing anything else but possibly the oil gauge .

PS , it looks like your MAF relay receives power from the fuel pump circuit so unplugging the switch & relay will result in no power to the MAF relay . It should still run , but it will throw a MAF code that will need to be cleared when you hook back up the switch & relay at the end of your procedure .

Last edited by OrangeBird; 03-02-2017 at 11:10 AM. Reason: edited to add the comment about the MAF
Old 03-02-2017, 01:16 PM
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Re: How to disable only the fuel pump?

Pull the ops connecter off.
Old 03-02-2017, 03:16 PM
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Re: How to disable only the fuel pump?

What is the ops connector?

Is there a connector near the back of the car that is easy to access?

Found this:

Connector C313: Below Center Of Rear Seat
Connector C207: Behind RH Side Of I/P, Near ECM

Last edited by Tootie Pang; 03-02-2017 at 03:21 PM.
Old 03-02-2017, 03:20 PM
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Re: How to disable only the fuel pump?

Oil pressure switch, there is the fuel pump connecter in front of the gas tank.
Old 03-02-2017, 03:48 PM
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Re: How to disable only the fuel pump?

Awesome, I'll look for that!
Old 03-02-2017, 03:52 PM
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Re: How to disable only the fuel pump?

From my manual:
As a back-up system to the fuel pump relay, the fuel pump can also be turned ON by the oil pressure switch. The oil pressure switch is a normally open switch which closes when oil pressure reaches about 28.0 kPa (4.0 psi). If the fuel pump relay fails, the oil pressure switch will power the fuel pump.

Bottom line: The fuel pump should be disabled at the fuel pump connector.



Last edited by Tootie Pang; 03-02-2017 at 03:55 PM.
Old 03-02-2017, 05:13 PM
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Re: How to disable only the fuel pump?

Originally Posted by Tootie Pang
From my manual:
As a back-up system to the fuel pump relay, the fuel pump can also be turned ON by the oil pressure switch. The oil pressure switch is a normally open switch which closes when oil pressure reaches about 28.0 kPa (4.0 psi). If the fuel pump relay fails, the oil pressure switch will power the fuel pump.

Bottom line: The fuel pump should be disabled at the fuel pump connector.


The relay is only there for ecm control of the 2 second prime.
After that cranking 4psi of oil pressure power directly from the fused battery lead goes to the pump.(not really a backup!).
Old 03-03-2017, 10:52 AM
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Re: How to disable only the fuel pump?

I found the connector to the fuel pump and level sender unit right above the rear axle pumpkin and the body panel. Easy to get to and worked like a charm. Thanks everyone. Got my injectors cleaned out.




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